1. The Field of the Invention
The present invention relates generally to wireless network amplifiers. More specifically, embodiments of the present invention relate to the use of a single amplifier for amplifying multiple wireless signals transmitted in different frequency bands.
2. The Relevant Technology
In recent years, cellular (“cell” or “mobile”) telephones have dramatically increased in popularity. A growing number of people are relying exclusively on cell phones, and are abandoning their traditional land line telephone services in favor of the convenience of cell phones. This increase in cell phone reliance places increased demand on network providers to provide reliable cellular signal coverage over a wider area.
Use of cell phones in areas having a weak signal often results in dropped calls which can be annoying for the cell phone user and expensive for the wireless service provider. Dropped calls often occur when the signal between the cell phone and the base station is lost. A loss of signal may occur for a number of reasons, including interference due to buildings or mountains, or an increase in distance between the cell phone and the base station. Therefore, a need exists to increase the reliability of cell phones near large buildings and in vehicles driving long distances in remote areas. There is a need to ensure that reliable signal coverage is provided in a wireless network. Eliminating dropped calls or increasing coverage is beneficial to the network provider.
Attempts have been made to increase the reliability of cell phones through use of cell phone signal boosters, also known as cellular network amplifiers. Cellular network amplifiers receive the cellular signal sent from a base station, amplify the signal, and retransmit the signal to one or more cell phones. Similarly, the cellular network amplifier receives the signals from one or more cell phones, amplifies the signals, and retransmits the signals to the base station.
Cellular network amplifiers are typically placed in relatively close proximity to cell phones, and serve the purpose of increasing the level of the signals being transmitted to and from the cell phones so that the cell phones can communicate with base stations that would otherwise be out of range. Some amplifiers are configured to be integrated with the cell phone itself or with a cell phone cradle. Alternatively, other amplifiers are configured to be placed in a separate location from the cell phone itself. For example, a cellular network amplifier may be placed in a user's vehicle, or in or near a building that otherwise may have poor reception.
Because different handsets may transmit signals in different frequency bands, it is often necessary to provide an amplification system capable of amplifying mobile telephone signals transmitted at different frequencies. For example, two common frequencies at which the handset may transmit include the cellular spectrum (i.e., 800-900 MHz) and the PCS spectrum (i.e., 1850-1990 MHz). One shortcoming common to many cellular network amplifiers is that they are often configured to amplify signals transmitted within a single frequency band. Therefore, mobile telephone signals being transmitted outside of the frequency band of the cellular network amplifier will not be amplified.
One technique for amplifying mobile telephone signals having multiple frequency bands includes using separate network amplifiers for each band. Another technique for amplifying mobile telephone signals having multiple frequency bands includes using a single network amplifier having multiple amplifier circuits, where each amplifier circuit is used to amplify a separate frequency band. Typically, a separate Monolithic Microwave Integrated Circuit (MMIC) amplifier is used to amplify each of the different frequencies. The use of separate amplifier circuits for each frequency band will usually result in higher manufacturing costs in addition to increased weight and size. Furthermore, the use of separate MMIC amplifiers often results in undesirably high noise levels.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.